Test device and method for torsional strength and shear strain of sand particle nano gel cementing area

The invention discloses a test device and method for torsional strength and shear strain of a sand particle nano gel cementing area. The test device comprises a torque applying device, a cementing area forming device, a particle image speed-measuring device and a data acquisition and control system. The torque applying device comprises a rotating shaft lever, a fine wire, a stress meter, a force applying rod and a linear ultrasonic motor; the cementing area forming device comprises a silica sol water tank containing a colored particle, a spherical particle, a particle mounting sleeve rod, a round section organic glass sleeve and a quartz glass plate; the particle image speed-measuring device comprises a digital camera and a light source; the data acquisition and control system is respectively connected with a load applying device and the particle image speed-measuring device. The invention designs the cementing area forming device applicable to shear strain non-contact measurement on a torsion section; by usi